After being listed as doubtful the first two weeks—and sitting out both games—New England Patriots tight end Rob Gronkowski is listed as questionable for Sunday's game against the Tampa Bay Buccaneers. Officially, it means he has a 50-50 chance of playing at Gillette Stadium.

Although he has been upgraded on the injury report, he has been limited in practice all week.

Gronkowski had an offseason full of physical problems, including multiple surgeries on his left forearm and a back procedure. If he doesn't return against the Bucs, he almost certainly will be back in the lineup for Sept. 29's Sunday night road matchup against the Atlanta Falcons.

The Patriots' offense sputtered without Gronkowski, as quarterback Tom Brady has become increasingly frustrated with a weak receiving corps that includes three rookie wideouts and a rookie tight end in significant roles.

The offense stumbled through a 13-10 victory over the New York Jets in Week 2, and Brady didn't hide his anger. After the game, he admitted that he must improve his body language. After two games, his passer rating is a lowly 74.1, as compared to his career rating of 96.3.

Given that wide receiver Danny Amendola, who has a history of health issues, is doubtful this week and is no certainty to return next week with a possible sports hernia, the outlook among Pats wideouts isn't favorable. That makes Gronkowski's return even more crucial. If he and Amendola can't stay healthy, the Patriots likely will struggle all season. It doesn't help that running back Shane Vereen is out half the season with a broken wrist.

In his three seasons, Gronkowski has 38 receiving touchdowns, the most in the NFL over that span. In league history, only Jerry Rice and Randy Moss had more receiving TDs in their first three seasons.

"He's a great player and he helps in the run game and the pass game, provides a level of toughness for our team, and he's been a really consistent player when he's been out there," Brady said early in the week on Boston radio station WEEI-FM. "So it's really—it's hard to replace him. There's only one Gronk. I know he's working his butt off to get back, and every time I see him he's got a great attitude about his rehabilitation and what he's going through to get back on the field."

Earlier in the week, ESPN reported that Gronkowski had a 50-50 chance of playing. ProFootballTalk.com reported the tight end was closer to doubtful (25 percent chance of playing) than questionable.